The present invention relates to a rotary electric apparatus having a structure which comprises a stator and a pair of rotors disposed at both-sides of the stator. And furthermore this invention relates to a generator and a motor respectively using the above rotary electric apparatus.
The applicant of the present invention had previously proposed a generator having a structure shown in FIGS. 12 and 13 as per the Laid-Open Japanese Patent Publication No. HEI-7-123662.
The generator comprises a pair of rotors 92N and 92S which are integrally secured onto a rotary shaft 90, spaced apart a certain distance, and a stator 91 disposed surrounding an external periphery of the rotors 92N and 92S.
The rotor 92N has N-polar magnetic poles 93a and 93b at diagonal positions of the external periphery. The other rotor 92S has S-polar magnetic poles 94a and 94b at diagonal positions of the external periphery. These magnetic poles are respectively formed outwardly.
The stator 91 has 4 cores 95a.about.95d disposed in a circle around external periphery of the rotors 92N and 92S wherein coils 96a.about.96d are respectively disposed at lengthwise center portions of the cores 95a.about.95d. Winding directions of the coils 96a.about.96d are arranged in such a manner in which, if the coils 96a and 96c disposed at diagonal positions were wound in the clockwise direction, then the coils 96b and 96d disposed at the other diagonal positions are wound in the counterclockwise direction.
When the rotors 92N and 92S are rotated by delivering rotating force to a rotary shaft 90 of the generator, as shown in FIG. 14 for example, sawtooth shaped inductive electromotive force V1 is generated from the coils 96a and 96c disposed at one of the diagonal positions, whereas similar inductive electromotive force V2 having lagged phase is generated from the coils 96b and 96d disposed at the other diagonal positions. By way of synthesizing inductive electromotive forces V1 and V2 generated in the coils 96a.about.96d, rectangular output power V is generated, and yet, by way of shaping waveform of the output power V, direct-current output power is generated.
Nevertheless, according to the structure of the above-referred generator, inasmuch as the rotors 92N and 92S are opposed to the stator 91 in diametric direction of the shaft 90, the cores 95a.about.95d of the stator 91, the magnetic poles 93a/93b of the rotor 92N and the poles 94a/94b of the rotor 92S are respectively formed with a curved surface. Thus much labor/time is needed for the manufacturing process, and magnetic fluxes from the magnetic poles 93a, 93b, 94a, and 94b are also unevenly distributed causing the generated output power V to be distorted, thus raising a problem.
In order to provide greater magnetic flux for the magnetic poles 93a, 93b, 94a, and 94b, it is essential that lengthy permanent magnets be used in the axial direction, but it in turn causes the size of the generator to be expanded further. Consequently, this results in an extended total length of the magnetic path resulting in iron loss and leakage flux increasing adversely affecting operating efficiency, thus raising a problem as well.